1. Field of the invention
This invention relates to an apparatus for attaching and detaching such exterior members as doors, a trunk, a bonnet, and fenders which can be openably mounted by means of such tightening devices as pins, bolts, etc. to a vehicle body, in the assembling line of vehicles.
2. Description of the Prior Art
In the assembling lines of vehicles, such exterior members as doors, fenders, a trunk and a bonnet are attached to a vehicle body through real parts matching. In this case, the exterior members are mounted to a vehicle body frame by means of such tightening devices as pins, bolts, etc. so that they can be opened and closed for the vehicle body frame. This aims at absorbing the dimensional errors and achieving smooth body lines. However dimensional errors will occur when attaching exterior members such as doors, etc. which are produced by a plate working press, to the vehicle body frame.
In the case of painting doors, fenders, etc. which are one of the examples of exterior members assembled as shown above, these doors and fenders are removed from the vehicle body frame, are handled as a single independent member, and are painted with the painting surface kept horizontally. After the paint is dried, these members are assembled again, thereby causing a vehicle body of which painting quality is excellent. This is because paint can be prevented from sagging down by painting with the exterior members kept horizontal.
In these assembling lines, in the case that doors, fenders, etc. are automatically disassembled and assembled, the automatic drawing out and insertion of pins, bolts, etc. and the holding of doors, fenders, etc. is necessary.
Hence, such an apparatus as shown in FIG. 29(a) and (b) has been recently developed.
The apparatus shown in FIG. 29 is used for attaching doors to the vehicle body frame. In the case of removing the doors from the vehicle body frame, another apparatus having such a structure similar to the apparatus shown in FIG. 29 is used to carry out the removal work.
Namely, in the apparatus shown in FIG. 29, a door (not shown) is kept by a pair of claws 351 and 351 attached to a fixture 350, another claw 353 attached to the base plate 352 and a pair of vacuum pads 354 and 354 attached to the base plate 352. The claws 351 and 351 supports a hinge portion installed at the vertical position of the door, respectively, and the claw 353 is inserted into the catch portion provided in the door. Besides, the vacuum pads 354 and 354 are for attracting the door body.
The setting angle of the fixture 350 is compensated by a position compensating mechanism 355, and the position of the claw 353 is also compensated by another position compensating mechanism 356.
A pin (not shown) is inserted by action of a set of claws 357 and 357 provided on the fixture 350 into the door held by the claws 351 and 353 and the vacuum pads 354 as shown in the above. As a result, the door is set to the vehicle body frame.
Also, the apparatus does not include a mechanism for detecting the position of the pin and another mechanism for keeping the pin. Therefore, it is necessary for an operator to support the pin after a robot moves to the position taught in advance.
Hence, in the conventional apparatus, as a mechanism for keeping a door and a mechanism for drawing out and inserting a pin are arranged on a common robot, there is some limits in the travelling distance and the distance of compensation thereof. Therefore, in case that the positional deviation of the pin for the vehicle body frame or a different type of vehicle comes on the assembling line, the apparatus does not cope with drawing out and inserting the pin. Therefore, there is a problem that the conventional equipment is short of universality for attaching a door to and removing it from a vehicle body frame.
On the other hand, as a fender is assembled to a vehicle body frame with bolts through real parts matching, the mounting position does not become uniform, and it is impossible to easily position the holding members to hold the fender for the fender.
In addition, there is some gap in the screwing position of the bolts among the vehicle body frames. For example, even though the bolts are tried to be automatically tightened and loosened by using a nut runner, it is impossible to accurately position the nut runner for the bolts when the nut runner is attached to a robot which can make only simple repeating actions.
For this reason, the automatic mounting and dismounting of a fender has not yet been realized.
In the assembling lines of vehicles, a trunk, a bonnet and the like are attached to the vehicle body frame together with doors, etc. through real parts matching in advance. In this case, for example, the trunk is supported by hinges fixed to the vehicle body frame by for example bolts, so that the trunk can be opened and closed for the vehicle body frame. This aims at absorbing the dimensional errors and finishing to smooth body lines though the dimensional errors are apt to occur when assembling the trunk, the bonnet, etc. which are made and formed by a plate-working press, to the vehicle body frame.
When painting the trunk, the bonnet, and the like that have been assembled as shown above, the trunk, the bonnet, etc. are removed from the vehicle body frame together with the hinges thereof, and the painting thereof is conducted as being handled as a single independent member so that the painting of the inside of the vehicle body can be easily carried out since such obstacles as a trunk, a bonnet, etc. have been removed.
In such an assembling line as shown above, in the case that a trunk and the like are automatically disassembled and assembled, it will be a great point to automatically handle the trunk and to automatically loosen and tighten the bolts.
However, as the trunk is in a closed position for the vehicle body frame in the assembling line, any clearance into which a plurality of holding members to hold the trunk are inserted is not formed between the trunk and the vehicle body frame. Hence, it is necessary to keep the trunk in the opened position thereof for the vehicle body frame. But as shown in the above, as the trunk is assembled to the vehicle body frame through real parts matching, uneveness may occur in the mounting position thereof, and it is impossible to easily position the holding members for the trunk.
Also, more or less unevenness may remain in the screwing position of the bolts among vehicle body frames. For example, even though the bolts are tried to be automatically tightened and loosened by using a nut runner, it is impossible to accurately position the nut runner for the bolts when the nut runner is attached to a robot which can make only simple repeating actions.
For this reason, it has not been realized to mount and dismantle a fender in an automatic manner yet.